El Behery 2015.

Study characteristics
Methods	Randomised controlled trial Single‐centre
Participants	Country: Egypt Population: women attending the outpatient clinic with abnormal uterine bleeding Age range 30 to 50 years N = 138 Inclusion criteria: age between 30 and 50 years old, those with histologically confirmed non‐atypical simple or complex endometrial hyperplasia, a desire to avoid hysterectomy, and no contraindications against progestin hormones Exclusion criteria: uterine anomaly, women with fibroids (more than 12 weeks' size or distorting the uterine cavity), malignancy, genital infection, liver disease or liver tumour (benign or malignant), thromboembolic disease, deep vein thrombosis, hypercoagulable state, a history of coronary artery disease, or myocardial infarction Recruitment from May 2011 to November 2012
Interventions	1. LNG‐IUD (Mirena, Bayer Schering Oy, Turku, Finland) (n = 60). Inserted in the uterine cavity in the postmenstrual phase in the outpatient department and kept in situ for 6 months versus 2. Dydrogesterone (Duphaston, Solvay pharmaceuticals B V, the Netherlands) (n = 78). 10 mg, 2 tablets twice daily orally from fifth day of menstruation for 21 days for 6 months
Outcomes	1. Regression of endometrial hyperplasia. This was measured by dilation and curettage biopsy at 6 months. The authors reported on recurrence of endometrial hyperplasia during a 12 months' follow‐up period. 2. Proportion of women undergoing hysterectomy 3. Adverse effects associated with hormones
Notes	After randomisation 18 women withdrew from the oral group before completion of the study because of non‐compliance to progesterone side effects, and another 2 women withdrew from the LNG‐IUD group because of noncompliance due to menstrual spotting. Therefore, the final studied group included 118 women – 18 women were lost to follow‐up and thus excluded, leaving a final 100 women completing the study (50 in each group) No financial support received Ethics approval obtained Informed consent obtained No trial registration or study protocol found
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomisation using computer‐generated random numbers. Randomisation uneven: "78 were assigned to receive oral progesterone and 60 were assigned to insert LNG‐IUD."
Allocation concealment (selection bias)	Unclear risk	Not stated.
Blinding of participants and personnel (performance bias): EH regression All outcomes	Low risk	No blinding/not possible; the review authors judge that the outcome (regression of endometrial hyperplasia) was not likely to be influenced by lack of blinding.
Blinding of participants and personnel (performance bias): Other outcomes All outcomes	High risk	For adverse effects, as per review protocol: "for subjective measures, if the patients are aware of the type of treatment they are on, and there is no placebo arm to the trial, then we will rate this as at high risk of bias."
Blinding of outcome assessment (detection bias): EH regression All outcomes	High risk	No blinding and the study does not provide information on those performing histological diagnosis or outcome assessment, and whether they were blinded to the treatment groups. As per review protocol: "if the pathologists reading the slides are aware of the type of treatment the patient is on, or it is not stated whether they are blinded, then we will rate this as at high risk of bias."
Blinding of outcome assessment (detection bias): Other outcomes All outcomes	High risk	Adverse effects and satisfaction were self‐reported. Hysterectomy rate was influenced by patient preference.
Incomplete outcome data (attrition bias) All outcomes	High risk	"After randomisation, 20 women withdrew (18 oral vs 2 IUS) and 18 were lost to follow‐up (10 oral vs. 8 IUS) which translates to 36% ([18+10]/78) attrition rate for the oral group and 17% 9[2+8]/60) attrition rate for the IUS group. Higher chance of patients continuing the LNG‐IUS treatment resulted in higher compliance and better efficacy in treating EH compared to oral progestogens".
Selective reporting (reporting bias)	Unclear risk	Side effects were asked but the time frame unclear. The reason for hysterectomy is unclear, whether hysterectomy rates linked to side effects.
Other bias	Low risk	Baseline characteristics reported and no obvious significant differences.